National Center on Educational Outcomes

Special Topic Area:
Accommodations for Students with Disabilities

Frequently Asked Questions

1. When should accommodations be used?
Accommodations should be provided to ensure that an assessment measures the students knowledge and skills rather than the students disabilities. Most often, these accommodations are ones that are routinely provided during classroom instruction. Accommodations should not be introduced for the first time during an assessment. Decisions about assessment accommodations should be based on what students need in order to be provided with an equal opportunity to show what they know without impediment of their disabilities.

2. Who makes the decision?
Most decisions about who needs assessment accommodations should be made by people who know the educational needs of the student. Federal law now requires that this be the Individualized Education Program (IEP) team. It is important, however, for a students general education teachers to provide input to accommodations decisions  even if they are not members of the IEP team.

3. What is the impact of assessment accommodations on score comparability?
With the growing database of research on accommodations (see NCEO Online Accommodations Bibliography), we are building empirical evidence of impact. Still, most states and districts use professional judgment to determine which accommodations affect score comparability. For example, reading a reading test aloud to the student when the reading test is measuring decoding generally is considered to change the nature of the task. The resulting score probably should not be compared to other decoding scores. However, if the test is measuring reading comprehension, the accommodation allows the student to demonstrate this skill without the barrier of disability. The resulting score likely could be compared to other students scores.

4. How fair is it to provide assessment accommodations to some students, but not others?
When answering this question, it is important to remember that the intent of providing accommodations is to "level the playing field" for students, ensuring that the test is measuring the students skills, not just the effects of disability. Some states have decided to extend availability of most accommodations to all students, not just those with disabilities. Variability in policies on assessment accommodations often is due, in part, to differences in definitions and test characteristics, as well as to variations in which accommodations are counted in accountability systems.

5. What is the difference between an accommodation and a modification?
Because we do not currently have national agreement on the terms used to refer to accommodations, the answer to this can differ by state. However, many states do define accommodation and modification in different ways. An accommodation generally refers to a change in the way a test is administered, or a change in the testing environment, with the added characteristics that the construct measured does not change. A modification generally refers to a change to the test that is thought to change the construct measured. It is important to remember that most states do not have empirical evidence about construct validity and accommodations, and that these distinctions are made by professional judgment, not empirical evidence.

6. How does the type of test (e.g., norm-referenced vs. criterion-referenced) affect assessment accommodation decisions?
Some states use norm-referenced tests (NRT), nearly all use criterion-referenced tests (CRT), and some use both. NRTs are used to allow comparisons to norms developed under standardized procedures; CRTs assess whether students can perform particular tasks, but do not compare a students performance with the performance of a standardization group.

NRTs create special challenges for providing accommodations because most of these tests have been standardized without allowing accommodations. As a result, most test developers indicate that raw scores from accommodated tests cannot be compared to those of the normative group. This is changing as test developers begin to allow accommodations during standardization. For those accommodations not included, states may need to report the scores separately.

CRTs are designed to measure performance in relation to standards, and thus should be more open to the use of accommodations. Similarly, reporting results from accommodated assessments with non-accommodated assessments should be acceptable. The No Child Left Behind Act of 2001 requires that student performance is assessed relative to grade-level academic content standards.

7. How are accommodated test scores reported?
Given the premise that accommodations are intended to allow the measurement of a students skill, and not the effect of a disability, scores can be aggregated to best capture the performance of all students. When the effects of particular accommodations are questioned, a reasonable approach is to both aggregate the data with the rest of the test scores and to disaggregate the scores of students receiving questionable accommodations.

8. What research is available on assessment accommodations?
Some states and policy organizations have conducted research on accommodations in large-scale assessments, and more and more university researchers are also studying accommodations. A comprehensive compilation of research on accommodations is contained in the NCEO Online Accommodations Bibliography. Until more research is available, states and districts are basing decisions on the legal requirements to provide accommodations, and what they see as best practice.

NCEO is supported primarily through a Cooperative Agreement (#H326G050007) with the Research to Practice Division, Office of Special Education Programs, U.S. Department of Education. Additional support for targeted projects, including those on LEP students, is provided by other federal and state agencies.

This document is provided for the user's convenience. Inclusion does not constitute an endorsement by the U.S. Department of Education of any views, products or services offered or expressed.